Side Fuel Tank Sending Unit Replacement

YachtTech82

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I believe I have a bad sending unit in the side tank of my 1990. The rear tank measures on the gauge from full to empty but side or front tank only shows empty. It seems there quite a few of these on the market and I don't know for sure which one to buy. Does it require a strainer and is that included? How big of a job is it to drop the tank? Depending on where you look online the picture shown looks different and I haven't been able to find a good source for info on what to buy. This is from rockauto which I think is correct, Tank sender
 

Clb

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Search here first, there's a metric tonne of fuel system threads here.
You will find part #'s quoted as well as multimeter specs
 

IDIBOBS

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Side tank sending unit part number FMSU-7DE. A quick google search found a few supplier’s. It looks like Jeff’s bronco grave yard has them new for around $80 as well as parts geek, Eclassics and even Amazon.

I have not found a single part yet that is not still mass produced for these trucks. They are not that old and not rare in any way.
 

dbg03

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I just did my sending unit on my '85. I got the sending unit off of ebay, I can't really advise well on what one would be a guaranteed fit. Dropping the tanks isn't so bad in these, I would imagine its even better if you don't live in the salt belt lol. I did mine alone while it was half full. I loosened the front strap until it was near the bottom of its threads, and then I took out the rear strap. I let the back of the tank down slowly, and then i pulled it backwards off of the front hanger until it was completely down. During reinstallation I slid the front end of the tank back up into the hanging strap, and hung up the rear with a car jack. One thing to note is that you're gonna need some fuel quick disconnect tool things to take off the lines, I forget their names. They slide over the hanger lines and push into the fuel line connector. I hope I explained some of this well and I wish you luck!
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Nero

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Chances are the float got a hole in it and sunk. If you want to save a few bucks, get just the float.
 

catbird7

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I think all of the "in tank" components are diesel specific, and sometimes difficult to locate and pricey. At least this was true years ago when I was searching. Difficulty finding shower heads is something that comes to mind, anyway the best solution for me was to convert everything to common off the shelf items used for gasoline system. Including purchasing two new plastic tanks {front & rear}. Had this set-up now for many years and zero problems. Parts are {were} way cheaper and widely available.
 

Old Goat

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This is where I have ordered my Sending units and Shower heads. $21 for Shower Heads, about the cheapest I have seen.
Ordered 4 and one rear sender for my 86, got it in the mail day
before yesterday, took a week to get here.
Here is where I have ordered them, looks like the inventory is
out of stock on some years.


They are OHM specific depending on the years.
Some come with the Shower Head, but no rubber gasket or new lock ring, others come with Lock ring, Gasket but no Shower head.

The little clips that hold the Fuel line to the sender, you can
pop them up with a small Screw Driver. If they break, Dorman sells new one`s at most all Auto Supplies. I had to, with the age these trucks are the old plastic becomes brittle.



Goat
 
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Nero

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Bronco graveyard sells diesel specific sending units. The float is not fuel specific.
 

YachtTech82

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Wow good info, thanks. I do have the set of fuel line disconnect tools already so good to go there. Do all these use a shower head? I'm pretty sure I will need a new one, mine likes to suck air if I park at an incline.
 

Old Goat

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I was checking the various vendors on the Sending units.
It use to be posted what the OHM reading is for the various years senders. The OHM for full and OHM reading empty.


Here is the Brass float from Dennis Carpenter.


I have seen them in Plastic also.


Goat
 
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